Climate science once again finds itself fighting with hockey sticks

A recent climate paper's set off a torrent of complaints. We look at why.

About a month ago, a team of scientists came out with a clearer picture of a story whose rough outlines we already knew. These researchers simply wanted to reconstruct the temperatures that the Earth experienced during the Holocene, the current warm period that started at the end of the last glacial period. Although the new perspective didn't include anything especially surprising, it set off howls of controversy on the Internet, which reached such intensity that the authors of the research felt they needed to publish an FAQ describing their work in more detail.

Why did all of this happen? Because the subject of the paper was the climate and amid their research, the authors found that we're experiencing an unusual warming. We'll take a look at the science behind the controversy, and explain why most of the controversy misses the point.

The paper, which we covered in some detail, focused on the planet's temperature during the Holocene. The glacial cycles are driven by changes in the planet's orbit and axis of rotation, and these effects can be calculated in some detail. These calculations suggest that the peak of the warming caused by orbital changes occurred over 5,000 years ago, and the planet has been slowly cooling since, with the next glacial era over 1,000 years still in our future.

And, largely, that's what the study, authored by Oregon State's Shaun Marcott, showed. Marcott used samples termed proxies that help track global temperatures—things like ice core records and sediment samples—from around the planet to create a reconstruction of global temperatures for the entire Holocene. And, in that reconstruction, the Holocene's temperatures peaked about 7,000 years ago, and have been declining since. Until recently, that is; the instrument record shows that the decline has experienced a dramatic reversal in the last 100 years.

Not only is the Marcott paper consistent with our expectations, but it is also consistent with a variety of reconstructions of climates that focused on the past 1,500 years. These studies of more recent times have used many more proxy measurements, and their methods have a much better temporal resolution, so they'd be expected to be more accurate than Marcott's study for the most recent years. Yet they and the Marcott study got essentially the same answer, which was "indistinguishable within uncertainty" from the other results, as the new paper put it.

So, there'd be plenty of reasons to think that the Marcott study was at least in the right ballpark, and a strong first attempt at this sort of all-Holocene global reconstruction.

Except there is one problem: the studies of the past 1,500 years are what created the so-called "hockey stick" temperature graph, which shows a dramatic uptick in recent temperatures. By replicating that result, the authors waded into what sometimes seems like an entire industry dedicated to convincing everyone that the hockey stick doesn't exist.

I don't want to believe

The response has been about what you'd expect. Steve McIntyre runs the "Climate Audit" website, and has devoted a lot of the material there to arguing against most of the scientific community's proxy reconstructions of historic temperatures. In the last month, he's published 10 blog posts that reference the Marcott paper. The less moderate "Watts Up With That" site has already run 19. Some of those are truly bizarre, such as one in which the global temperatures are compared to a single site in Greenland; the title of another asks, "How long before Science has to retract Marcott et al?"

Unfortunately, almost all of the controversy was completely off-target, and a lot of it displayed a significant misunderstanding of the claims of the Marcott paper.

Most of the ire is focused on the blade of the hockey stick, the sudden rise in temperatures that has occurred over the last century or so. We know it has happened because of the instrument record and a large number of global changes in ice volume, species ranges and migrations, etc. And some of the rise shows up in most proxy records, including the one generated in the Marcott paper.

But the uptick in the Marcott proxy records isn't the main point of the paper. In fact, the authors clearly say that their data there is pretty limited. To begin with, they had to stop their reconstruction in 1950 because the proxies more or less give out then (we'll get to that in more detail below). And, even in the decades before that, they note that the data is very uncertain because of "the [limited] temporal resolution of our data set and the small number of records that cover this interval." In fact, for the figure shown in the paper, the team interpolated some data in order to fill out the sparse records; if they hadn't, the warming would have been over half a degree Celsius higher. In other words, they took steps to underplay the recent warming.

An example of layers in ice.

Why is the record so poor? It's a product of the sort of proxies used in longer term studies. To give a specific example, we can look at the ice cores. The layers in the ice form annually, and are relatively easy to distinguish; major events like volcanic eruptions provide clear markers of specific years. So, the temporal resolution of the ice is good. It's just that the temperature record isn't. That's derived from the isotopes in gasses trapped in air bubbles that form in the ice. But these air bubbles can exchange some limited amounts of gas with the atmosphere for over 200 years after they form. So, the record isn't a single sharp point, but rather a somewhat weighted average of decades. And there are essentially no records that are current—the ice simply hasn't sealed off yet.

Similar things apply to other records used in the study, like sediment cores. As a result, if you're looking for a hockey stick, the Marcott record shows a hint of it, but it's not one that we should place high confidence in, as the paper itself makes clear. And yet, oddly, that's precisely the point of the paper that has attracted almost all the controversy.

Missing the forest for the hockey sticks

Even the more scientifically literate criticisms on these sites have included vague hints of conspiracy from Marcott and the scientists who've found results like his. Steve McIntyre at Climate Audit has highlighted how many of the temperature records were re-dated compared to their original values, which he's implied was done in a way that specifically creates an artificial hockey stick. But the re-dating was done based on carbon-14 radioactivity dating, and uses software that's produced by someone else—and that software has been posted online for at least the last two version releases. If there were a conspiracy involved in the re-dating, it's a pretty poorly conceived one. And it doesn't mean that the new paper is right, just that the tools needed to show it's wrong are available to anyone.

In any case, this criticism is also focused on the hockey stick trajectory, which the paper itself said wasn't a very robust result. Nevertheless, it generated so much attention that the authors of the paper felt compelled to respond, posting an FAQ at the RealClimate blog. In this, they go into far more detail about why the 20th century record shouldn't be considered the key point of this work:

(1) the different methods that we tested for generating a reconstruction produce different results in this youngest interval, whereas before this interval, the different methods of calculating the stacks are nearly identical (Figure 1D), (2) the median resolution of the datasets (120 years) is too low to statistically resolve such an event,(3) the smoothing presented in the online supplement results in variations shorter than 300 yrs not being interpretable, and (4) the small number of datasets that extend into the 20th century (Figure 1G) is insufficient to reconstruct a statistically robust global signal...

So, the tail end of the temperature graph (the bit that shows a rise in 20th century temperatures) that came out of this study shouldn't be viewed as especially significant. And the people who are obsessing about it are misdirecting their energies.

See Clive Best's blog for an alternate reconstruction of the method's ability to resolve century sized spikes:http://clivebest.com/blog/

I am not sure how we can claim that we can somehow reconstruct the short term variability of climate from a long term low time resolution proxy reconstruction. Marcott is not comparing recent temperatures to historical climate data, he's comparing it to a statistical simulation of data, a very different animal.

Completely aside from the blog-controversy over hockey sticks and the like, for some reason I am fascinated by the proxy reconstruction of holocene temperatures as a whole, especially the fact that, assuming only on the normal cyclical behavior, the big freeze is almost here.

It is kind of weird to look back at recorded human history and think about the fact that everything humanity has experienced as "normal" in the last 4-5 thousand years is really just a short-term warm spell in the middle of the very cold, very nasty, very non-conducive to civilization true norm.

I expect the long-term result of current climate science will be the eventual stabilization of temperatures at some level we find comfortable and then the permanent (so long as humanity remains capable of it) artificial staving-off of the ice.

See Clive Best's blog for an alternate reconstruction of the method's ability to resolve century sized spikes:http://clivebest.com/blog/

I am not sure how we can claim that we can somehow reconstruct the short term variability of climate from a long term low time resolution proxy reconstruction. Marcott is not comparing recent temperatures to historical climate data, he's comparing it to a statistical simulation of data, a very different animal.

Hmm...I don't get it. I am not sure what Tamino's debunking of Clive Best's data is, but just looking at that graph, even the largest peak in the data is less than half as large as the smallest synthetic peak. And the MWP he points to is way smaller, and spread out over a longer period of time.

You would think if a 0.9deg spike was hidden in the data, then at least one peak in the data would come close to at least the smallest synthetic peak (you'd probably expect it to exceed at least one synthetic peak). That graph seems to be showing the opposite of what Best seems to be claiming.

«context isn't really needed in order to motivate action on carbon emissions. Carbon dioxide is clearly a greenhouse gas, one that equally clearly acidifies the oceans. We've obviously been sending vast quantities of it into the atmosphere»

Let's try this:

Quote:

context isn't really needed in order to motivate action on salt. Salt is clearly a hypernatraemia-causing substance, one that equally clearly can cause seizures and death. We've obviously been sending vast quantities of it into our stomachs.

Timmer is sometimes a thoughtful writer, but by ignoring that there are or probably exist other carbon regulating mechanisms in the planet, he shows his true colors: alarmist. Does he genuinely believe that the Earth's carbon cycle is as simple as he implies it is his the paragraph above?

And you think no one has ever thought that may have been the case over the last 30 years? (1) We Know carbon has been increasing in the atmosphere (2) Can you point to some of these carbon regulating mechanisms which counteract the release of carbon buried in the ground over millions of years into the atmosphere (3) if CO2 amounts in the atmosphere was at a local equilibrium before humans started transferring vast amounts from underground to the atmosphere, it wouldn't be surprising if all those "regulating" effects only served to exacerbate the greenhouse problem.

«context isn't really needed in order to motivate action on carbon emissions. Carbon dioxide is clearly a greenhouse gas, one that equally clearly acidifies the oceans. We've obviously been sending vast quantities of it into the atmosphere»Let's try this:

Quote:

context isn't really needed in order to motivate action on salt. Salt is clearly a hypernatraemia-causing substance, one that equally clearly can cause seizures and death. We've obviously been sending vast quantities of it into our stomachs.

I'm not sure what point you think you're making here. Regulation of sodium intake is commonly prescribed for patients at risk for heart diseases or those with high blood pressure. You know, a very good analogy can be made between our current path of carbon emissions and someone who consumes way more salt than is healthy for themselves. Likening action on CO2 to reducing one's sodium intake is a clever way to advocate emissions controls.

Quote:

Timmer is sometimes a thoughtful writer, but by ignoring that there are or probably exist other carbon regulating mechanisms in the planet, he shows his true colors: alarmist. Does he genuinely believe that the Earth's carbon cycle is as simple as he implies it is his the paragraph above?

The Keeling Curve clearly indicates that natural carbon regulating mechanisms can't keep up (only about half of our emission are taken in by sinks each year, leaving the rest to accumulate like interest on savings account), so again, what's your point?

«context isn't really needed in order to motivate action on carbon emissions. Carbon dioxide is clearly a greenhouse gas, one that equally clearly acidifies the oceans. We've obviously been sending vast quantities of it into the atmosphere»

Let's try this:

Quote:

context isn't really needed in order to motivate action on salt. Salt is clearly a hypernatraemia-causing substance, one that equally clearly can cause seizures and death. We've obviously been sending vast quantities of it into our stomachs.

Timmer is sometimes a thoughtful writer, but by ignoring that there are or probably exist other carbon regulating mechanisms in the planet, he shows his true colors: alarmist. Does he genuinely believe that the Earth's carbon cycle is as simple as he implies it is his the paragraph above?

XavierItzmann is sometimes a thoughtful reader, but by ignoring that there exists 150 years of established physics and chemistry, (s)he shows his/her true colors. Does (s)he genuinely believe that the Earth's carbon cycle is so utterly mysterious as (s)he implies it is in the comment above?

Shame on John Timmer for not getting both sides of this story. I have been over to Climate Audit and looked at Steve McIntyre response to the Marcott paper. From what I see Steve is on much firmer ground than Marcott. If you are interested in both sides then look at: http://climateaudit.org/2013/03/16/the- ... g-service/ Keep in mind that this is the initial response. It gets worse as other experts and the owners of the core data start in on the problems with the paper.

Yeah John, don't just give us the factual stuff, please give equal coverage to the made up stuff too!!!!1!

"there'd be plenty of reasons to think that the Marcott study was at least in the right ballpark"

Boy, what a rigorous scientific standard climate science has set.....theories in the "ballpark" are presumptively correct...

It sure seems that somebody stopped reading the article before it went into illuminating discussions about how science is an iterative process and no single paper makes an idea scientific fact or not. It almost seems as though somebody stopped reading before the part about how totally expected and well-aligned with previous studies, evidence, and informed expectations this paper turned out to be, but that can't be right. After all, that was said several times before the sentence somebody just quoted.

Didn't bother to look did you. The Marcott paper took ice core data and redated it without the permission of or the help of the original owners of the data. As soon as you put the data back to the original form the spike at the end disappears. The criticism of this paper is valid and growing.

Am I the one missing something, or does it seem like the repeated and clearly-stated emphasis that "the spike at the end" wasn't the basis of this paper's conclusions is being ignored?

Didn't bother to look did you. The Marcott paper took ice core data and redated it without the permission of or the help of the original owners of the data. As soon as you put the data back to the original form the spike at the end disappears. The criticism of this paper is valid and growing.

Yeah, actually I (regrettably) wasted a couple of minutes looking over the link and its the usual McIntyre bs where he does his usual hand waving and misdirection act to try and distract from the substance of real science with arguments over minutia. But you are right, once you linked to climate audit I could have just called BS and rested comfortably knowing the balance of probability was I'd be correct. Would have saved a few minutes and denied SM a click through. Will take your advice next time.

Didn't bother to look did you. The Marcott paper took ice core data and redated it without the permission of or the help of the original owners of the data. As soon as you put the data back to the original form the spike at the end disappears. The criticism of this paper is valid and growing.

Didn't bother to read the article, did you? Especially the part which explained the dating, including the reference to the software used, allowing anyone to reproduce the results. Like in science.

The Keeling Curve clearly indicates that natural carbon regulating mechanisms can't keep up (only about half of our emission are taken in by sinks each year, leaving the rest to accumulate like interest on savings account), so again, what's your point?

Actually, Keeling in 1960 failed to realize that there are natural, massive carbon sinks. He, like Timmer, did not realize there is a complex carbon cycle, a cycle not yet understood.

In 2004, one year before Keeling passed away, Sabine et al. posited that the natural, massive carbon sinks that exist actually do capture 50% (at least in the extremely short geological timescale since the Industrial Revolution). But what other mechanisms do exist that only come into play in longer timescales?

If you don't know, why are you relying on them to denounce CO2 emissions controls?

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Are we even sure that CO2 deltas precede climate change or is it the other way around?

Seeing as how we're experiencing this right now, and it is totally expected from basic physics, and has not been found to contradict any empirical findings, and all of this is backed up by thousands of papers examining the issue... I'm gonna say that OUR carbon emissions are indeed the cause of this recent climate change. You might try looking into the many attribution studies that quantify various forcings at work on the climate, if you are genuinely curious about the issue. But you're not.

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Even as Man injected more CO2 into the atmosphere at a faster rate in the last 15 years than ever before... temps have held flat. Ooops.

Geez, it's almost as if carbon dioxide isn't the only thing acting on very short timescales! What a revolutionary idea! Not. We already know this, why you pretend that it's otherwise I can only explain as the same kind of escapist fantasy which lets WaltC denounce the fact of evolution. You are ignoring the tremendous amount of scientific knowledge we already have so that you can pretend we're more uncertain than we are. I'm sure you want us to take into account the other things that act to move the temperatures up and down over these 15-year spans of time. Guess what? When we do that, the warming signal is even more pronounced and clear. It's more than statistically significant over the last 15 years when we look at the relevant data, with the relevant knowledge.

Whoops! Furthermore, it's become evident that the vast bulk of heat retained thanks to our enhanced Greenhouse Effect is being stored in the oceans for now. Even as surface temperatures can show deceptive lack of trends for very short time intervals (like 15 years), the oceans don't.

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The larger point is that amidst all of this uncertainty, partisans advocate blind, economically crippling immediate action. What's the expression Timmer used? Ahh, yes, «context isn't really needed in order to motivate action on carbon emissions».

It's funny how you quote that part... OUT OF CONTEXT. A more blatant example of hypocrisy and ineptitude would be hard to come by. Thanks for demonstrating your total inability to make an honest argument. Seriously, I can't think of a better way to show your aggressively willful ignorance any more clearly than you just did by that little out-of-context quote mine. Quite brilliant, really. Let's add that to your example of eating too much salt as a way to argue for carbon dioxide caps.

Robert Westfall wrote:

Am I the one missing something, or does it seem like the repeated and clearly-stated emphasis that "the spike at the end" wasn't the basis of this paper's conclusions is being ignored? The paper was heralded as a confirmation of the hockey stick. With the spike at the end removed all you have left is long slow cooling trend.

You're wrong, and the reason why you're wrong was spelled out int he article on which you're commenting. The authors themselves did not use that spike; they used OTHER DATA from proxies and the instrumental temperature record. When we leave off their spike, "all you have left" is the thermometer readings and other researchers' proxy reconstructions which all agree that there is a massive spike after a long cooling period. Gosh, is that all? All we're left with is ... a hockey stick. I guess you sure showed us!

Robert Westfall wrote:

steell

Right we agree. Then why was the paper used to confirm current global warming? The authors used very questionable methods to graft current temperatures onto historic data. When called on it they circled the wagons.

Actually they didn't use any questionable methods at all. Comparing their reconstruction, other peoples' reconstructions, and the temperature record when all three cover overlapping time periods and have robust data, they are in agreement. This paper wasn't "used to confirm current global warming," this paper was used to cover the temperature history of almost the entire Holocene. The fact that it does, incidentally, confirm current global warming is just a side effect of the fact that it describes reality.

Right we agree. Then why was the paper used to confirm current global warming? The authors used very questionable methods to graft current temperatures onto historic data. When called on it they circled the wagons.

The "spike" was considered uncontroversial in the scientific community because it didn't conflict with the already well established increase demonstrated by several other methods. Its support of global warming comes from the fact that the paper clearly established that the temperature rise attributed to coming out of the last ice age peaked thousands of years ago, and we have been cooling since.

Many other studies have demonstrated that cooling reversed itself dramatically in the last century, This gives lie to the claim that warming over the last century is just part of the normal process of coming out of the last ice age.

Sheesh. To make the point in as simple terms as possible for any (theoretically) open-minded denialists out there: this paper isn't about recent temps. It is about what was happening BEFORE global warming, and it both agrees with and strengthens our understanding of that period better: the earth was cooling.

Other papers have established what has been happening AFTER global warming got started: the earth is warming. In the tiny region where they overlap, the confidence is small but to that extent they agree- a nice but minor, expected, and uncontroversial point.

The "hockey stick" is what happens when you put together a previous cooling trend (now better established) and the current warming trend (now very well established): the slope changes, you get a bend.

How hard is this to understand? Denialists are always complaining about the quality of data before 1900; now we get an improvement in our understanding of that period, and surprise, it supports and strengthens our previous understanding. The little shadows of ignorance the denialists skulk in and depend on are shrinking away.

The thing I don't get from most of these articles: What temperature is the Earth supposed to be? I've seen shows which talk about pre-historic creatures living in a sea that covered the Midwest. Does that mean that the sea level is too low? And if that's the level the sea is supposed to be, and hotter temperatures mean that the sea levels rise, doesn't that mean that the Earth is actually too cold right now? So global warming would just be a correction then, right?

I't not supposed to be any specific temperature for the sake of the earth, though it is "supposed" to be within a specific temperature interval to support us humans and our way of life. The earth will live on (earth does not care) if global temperatures rise 20°C, but human agriculture and our civilisation in general is dependant upon a number of crops and animal (actually, most of them) that we had yesterday. Any change from that status quo will have long-time detrimental effects on our ability to uphold our way of life.

The earth was slowly heading into a new ice age, but then something extraordinary happened, it started warming at an extreme and unprecedented rate.

The thing I don't get from most of these articles: What temperature is the Earth supposed to be?

There is no "temperature it's supposed to be." However, over the last 10,000 years or so, the temperature has been relatively stable and lacking in the kind of very rapid and drastic swing we're seeing lately. It has probably been warmer than today during that time, but then again it's very, very unlikely to have changed so quickly as it is now. And going forward, the change will only become more drastic. By the way, those ~10K years of relatively stable, slowly-changing climate? This is the entire time that human civilization has existed. Agricultural society has probably never seen temperature swings this drastic, this quickly. We are also moving into a temperature regime that humanity has never seen period, civilization or no. Without taking steps to limit our carbon emissions we are looking at a warming that's as far ahead of today's temperatures as today is from the depths of the last glaciation (or "Ice Age" as people tend to think of them), when glaciers covered Chicago in ice a mile thick. We're likely to see that kind of temperature regime by the turn of the next century. And warming will not stop just because of the extra zero in the calendar date. Most life, and most societies, can adapt to changing temperatures provided there is enough time. The rate of change is what's worrying, not just the magnitude.

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I've seen shows which talk about pre-historic creatures living in a sea that covered the Midwest. Does that mean that the sea level is too low? And if that's the level the sea is supposed to be, and hotter temperatures mean that the sea levels rise, doesn't that mean that the Earth is actually too cold right now? So global warming would just be a correction then, right?

The Earth is only "supposed" to be the temperature that certain factors conspire to make it at any point in time. It's just physics. The Snowball Earth epochs, when the entire planet was covered in snow, are just as natural as the Hothouse epochs when there was no ice at the poles at all. The planet was either that cold or that warm because of the physical factors which controlled its temperature. The main problem is that with our CO2 emissions enhancing the greenhouse effect, we're changing the temperature that the Earth is "supposed" to be at. With this much CO2 in the atmosphere, it's "supposed" to be warmer. Hence, the planet is currently warming up.

It's not that there is some universally ideal which must always be maintained for life to be perfect. Life adapts to the temperature it's in. Mammoths from the last "Ice Age" wouldn't find today's temperatures very comfortable outside of the Arctic, and dinosaurs from the Hothouse eras wouldn't find it very comfortable outside of the tropics. But if you changed the temperatures on them over just a few centuries instead of many thousands or millions of years, it's not like they can just step on the evolutionary accelerator and adapt instantly. Drastic, abrupt climate changes cause extinctions and ecosystem disruptions. It has already happened in the past, with lesser changes than the one we're looking at today. Now consider that over all of the history of human civilizations with our domesticated crops and animals we depend on for a stable, steady source of food, the climate has not changed as rapidly as it is today or will in the near future. There is good reason to be concerned about the rate of climate change we're looking at.

Did you guys see the part where he just totally ignored the bit about using our actual knowledge of how the climate works to account for recent temperatures, then went on to say that we don't know how to account for recent temperatures? Oh, and then he insisted that he didn't take Dr. Jay's quote out of context by completely ignoring the context of the full quote he himself provided.

The thing I don't get from most of these articles: What temperature is the Earth supposed to be? I've seen shows which talk about pre-historic creatures living in a sea that covered the Midwest. Does that mean that the sea level is too low? And if that's the level the sea is supposed to be, and hotter temperatures mean that the sea levels rise, doesn't that mean that the Earth is actually too cold right now? So global warming would just be a correction then, right?

The Earth isn't supposed to be any particular temperature. The question is what kind of climate conditions are best for human civilization. The answer is a stable climate.

Our infrastructure and agricultural systems are based upon a relativly stable climate. A small amount of warming is also worse than a small amount if cooling because of storm severity associated with extra warmth.

Keep in mind that human civilization arose in part due to a relatively stable climate.

The Earth is not "too cold right now". If we do, someday, decide on an optimal average global temperature for the planet to, for example, optimize food production, we would need to approach that equilibrium point slowly. But that kind of precise planetary engineering is well beyond our capabilities for now.

In the meantime, the best we can do is to prevent too much change to our climate over a short period of time. That means limiting CO2 output for now.

But what other mechanisms do exist that only come into play in longer timescales?

If you don't know, why are you relying on them to denounce CO2 emissions controls?

But do you know? Emissions controls are not cheap, and their cost burdens the poor disproportionally. Are you willing to sacrifice the poor in the altar of poorly understood CO2 mechanisms

No, that's not a logical conclusion.

The case you're attempting to make is that (1) assuming climate change is a real thing, then (2) emissions controls implemented today will impact the poor out of proportion to the not-poor. The opposite of (2) could well be true, given (1).

You haven't shown that the poor would be better off under (1), so logically your point is invalid. I could easily argue that the poor will be impacted either way and the two situations are likely to be equivalent.

At least we get to direct the impacts by making changes today. Maybe we can make a change that won't be so bad. That's a matter of imagination, something Humans are good at.

I also enjoy your consistency in applying religious metaphors to the scientists and people arguing that climate change is a real, man-made issue. It is a tried and true trolling tactic, and you employ it to some effect in nearly every post you make on this issue.

So is climate science about maintaining the earth at a temperature which is historically normal or historically abnormal? I just want to know whether turning down the thermostat (and reducing my carbon emissions) is helping nature or trying to thwart nature. If it's trying to thwart nature I might as well turn the heat up. Nature always wins.

Climate science is about understanding what has happened, is happening, and will happen to our climate. Climate policy is about doing what is best for our society, minimizing the impact of climate change on things like food production and infrastructure.

"Nature" isn't some sort of god or entity we are trying to thwart. Humans, and everything we do, are part of nature. By taking CO2 out of the ground and dumping it into the atmosphere we are changing our natural world (nature). Those changes are bad for our civilization.